/Engine/Source/Runtime/GeometryCore/Public/MeshQueries.h
Expand selection of vertices with one-ring neighbors.
static void ExpandVertexSelectionToNeighbors ( const TriangleMeshType & Mesh, const [TArray](API\Runtime\Core\Containers\TArray)< int32 > & Selection, [TArray](API\Runtime\Core\Containers\TArray)< int32 > & ExpandedSelection, [TMap](API\Runtime\Core\Containers\TMap)< int32, int32 > & VIDToExpandedSelectionIdx )